Non-Caloric Sweeteners and Weight Management

Non-caloric sweeteners have been researched extensively and have been found to be safe to use. However, their use as a weight-loss tool is still unclear.

Article By: The Weight Watchers Research Department

People often ask two questions surrounding non-caloric sweeteners, commonly referred to as artificial sweeteners: "Are they unhealthy?" and "Will they help me lose weight?" While there is conclusive evidence regarding their effect on health, their role in weight management is controversial.

Non-Caloric Sweetener Safety
The Center for Food Safety and Applied Nutrition section of the Food and Drug Administration (FDA) carefully evaluated the safety of non-caloric sweeteners and has approved the use of acesulfame-K, aspartame (e.g. NutraSweetTM), neotame, saccharin (Sweet‘N LowTM), sucralose (e.g. SplendaTM) and stevia. Many other leading health organizations, including the American Dietetic Association through its Evidence Analysis Library, have also found these ingredients to be safe. 1

Non-Caloric Sweeteners and Weight Management
The idea that replacing sugar with non-caloric sweeteners can help to reduce calorie intake and lead to weight loss is a common belief. In fact, there have been literally hundreds of studies of non-caloric sweeteners and their effect on weight management, metabolism, appetite, and obesity. The results of these studies vary considerably. While some studies show a beneficial impact on weight loss, others have found no impact. Still others find that these sweeteners actually promote weight gain.

Most studies that have shown a beneficial effect on weight loss have been short-term trials lasting from a few hours to 2 days. 2 Because of the short length of the study, it is problematic to conclude that non-caloric sweeteners are helpful over the long term.

There are several theories as to why non-caloric sweeteners may have no effect on weight or even lead to weight gain. Foods and beverages with non-caloric sweeteners can help people to eat fewer calories only when they are substituted for higher calorie foods and drinks. 3 People who use non-caloric sweeteners tend to be heavier, but this does not mean that these sweeteners cause weight gain.

Some research with lab rats has suggested that these sweeteners may interfere with the body's natural ability to regulate food intake, which may lead to overeating; however, this theory has not been tested in humans. 4 Other reasons could be related to behavioral factors with the idea that while drinking a diet soda pop or eating a reduced-calorie food may seem like it would be beneficial to weight loss, many people may find it more "acceptable" or that it "gives them permission" to eat more (e.g. diet coke with a fast-food combo meal. If nothing else is done but switching to a diet soft drink, weight loss is not likely.

Bottom Line
When taken together, research suggests that non-caloric sweeteners do not alter metabolism but their effect on appetite regulation is not fully understood. They can be used as a long-term weight-loss tool as long as they are in foods and drinks that help reduce total daily calories.